U.S. patent application number 10/523533 was filed with the patent office on 2006-05-11 for electronic product, a body and a method of manufacturing.
Invention is credited to Philip Rene Leurs, Franciscus Gerardus Coenradus Verweg, Johannus Wilhelmus Weekamp.
Application Number | 20060097376 10/523533 |
Document ID | / |
Family ID | 31502774 |
Filed Date | 2006-05-11 |
United States Patent
Application |
20060097376 |
Kind Code |
A1 |
Leurs; Philip Rene ; et
al. |
May 11, 2006 |
Electronic product, a body and a method of manufacturing
Abstract
The electronic product comprises a body with a three-dimensional
shape that is derived from the product. The body is provided with a
pattern of conductors including contact pads and at least one
electric element, in which the conductors are mechanically anchored
in the body. It is preferably provided with attachment means for
any carrier or external component. The pattern of conductors is
primarily provided at the surface of the body. Conductors can be
hidden inside the body, by removing in that area a releasable layer
attached to the conductors before instead of after the molding
process.
Inventors: |
Leurs; Philip Rene;
(Heerlen, NL) ; Weekamp; Johannus Wilhelmus;
(Eindhoven, NL) ; Verweg; Franciscus Gerardus
Coenradus; (Heerlen, NL) |
Correspondence
Address: |
PHILIPS ELECTRONICS NORTH AMERICA CORPORATION;INTELLECTUAL PROPERTY &
STANDARDS
1109 MCKAY DRIVE, M/S-41SJ
SAN JOSE
CA
95131
US
|
Family ID: |
31502774 |
Appl. No.: |
10/523533 |
Filed: |
August 5, 2003 |
PCT Filed: |
August 5, 2003 |
PCT NO: |
PCT/IB03/03157 |
371 Date: |
February 2, 2005 |
Current U.S.
Class: |
257/690 ;
257/E23.065; 264/272.14; 438/126 |
Current CPC
Class: |
H05K 2201/09118
20130101; H05K 1/183 20130101; H05K 1/0284 20130101; H05K 3/20
20130101; H05K 2201/09063 20130101; H05K 1/0274 20130101; H01L
2924/0002 20130101; H01L 2924/09701 20130101; H05K 2203/302
20130101; H01L 2924/0002 20130101; H01L 23/4985 20130101; H01L
2924/00 20130101 |
Class at
Publication: |
257/690 ;
264/272.14; 438/126 |
International
Class: |
H01L 23/48 20060101
H01L023/48; B29C 45/14 20060101 B29C045/14; H01L 21/50 20060101
H01L021/50 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 5, 2002 |
EP |
0207810.8 |
Claims
1. An electronic product comprising a body provided with a
three-dimensional shape that is derived from the product and
incorporates structurally at least part of the product shape, which
body comprises an electrically insulating material and comprises a
pattern of electrical conductors, which pattern includes contact
pads for external contacting which conductors are mechanically
anchored in the body, a plurality of electric elements being
encapsulated in the body and being electrically connected to the
pattern of electrical conductors.
2. An electronic product as claimed in claim 1, characterized in
that means are present for mechanical attachment of a component or
carrier to the body.
3. A body as claimed in claim 2, wherein the pattern of conductors
includes contact pads for contacting a component that can be
assembled to the surface of the body, and wherein the shape of the
body is fitted for assembly of the component.
4. An electronic product as claimed in claim 1, characterized in
that a sensing or transmitting first element is provided at the
surface of the body for radiation of a first kind and an auxiliary
second element for processing or providing of the radiation, the
first and second element having a predetermined spatial
interrelationship to each other to allow their functioning, which
is defined in the body, the first element being electrically
connected to the pattern of electrical conductors in the body.
5. An electronic product as as claimed in claim 1, wherein further
a separate signal processing unit is provided in or at the surface
of the body.
6. A body suitable for use as a product part in a desired product
and provided with a three-dimensional shape that is derived from
the product and incorporates structurally at least part of the
product shape, which body comprises an electrically insulating
material and comprises a pattern of electrical conductors, which
pattern includes contact pads for external contacting which
conductors are mechanically anchored in the body, a plurality of
electric elements being encapsulated in the body and being
electrically connected to the pattern of electrical conductors,
wherein the conductors are present at a surface only partially.
7. A body as claimed in claim 6, wherein the contact pads for
external contacting are exposed at a surface of the body.
8. A body as claimed in claim 6, wherein means are present for
mechanical attachment of a device, component or carrier to the
body.
9. A method of manufacturing a body suitable for use as a product
part in a desired product and provided with a three-dimensional
shape that is derived from the product and incorporates
structurally at least part of the product shape, comprising the
steps of: providing a foil having a releasable layer and a pattern
of conductor tracks, the pattern comprising an first area that is
to be hidden in the body; removing the releasable layer from the
first area to the extent that any conductor tracks; attaching
electrical elements to the conductor tracks; providing the body of
electrically insulating material by a molding technique, therewith
encapsulating the electrical elements and mechanically anchoring
the conductor tracks in the body; and removing the releasable layer
to the extent that it is present at a surface of the body.
10. A method as claimed in claim 9, wherein the releasable layer is
removed from the first area by cutting the releasable layer in a
pattern which is substantially corresponding to the pattern of the
conductor tracks in the first area.
11. An electrically insulating body provided with a conductor
pattern, which body acts as a carrier of the conductor pattern and
as a carrier of elements embedded in the body and/or components
assembled to the body, which body includes a rigid portion and a
flexible portion, in which rigid portion the body comprises a
non-elastic electrically insulating material and in which flexible
portion the body comprises an elastic, electrically insulating
material.
12. An electrically insulating body as claimed in claim 11, wherein
the flexible portion comprises conductors according to a desired
pattern.
13. An electrically insulating body as claimed in claim 11, wherein
the flexible portion is provided between a first and a second rigid
portion.
14. An electrically insulating body as claimed in claim 11, wherein
the pattern of conductors is at least partially present at a
surface of the body.
15. An electronic device comprising the electrically insulating
body as claimed in claim 11, and an electric element that is
assembled to the body or embedded in the body.
16. A method of manufacturing an electrically insulating body
provided with a pattern of conductors, the body having a flexible
portion and a rigid portion, comprising the steps of: providing a
foil having a releasable layer and a pattern of conductor tracks;
placing the foil in a first mould such that the pattern of
conductors faces away from a surface of the mould, and providing a
first electrically insulating material in the mould, the first
material becoming rigid after finalization of the molding
operation, therewith generating the rigid portion of the body
placing the thus partially molded foil in a second mould and
providing a second electrically insulating material in the mould,
the second material being elastic after finalization of the molding
operation, therewith generating the flexible portion of the body,
and removing the releasable layer to the extent that it is present
at a surface of the body.
Description
[0001] The invention relates to an electronic product comprising a
body provided with a three dimensional shape that is derived from
the product and incorporates structurally at least part of the
product shape.
The invention also relates to a body suitable for use as a product
part in a desired product and provided with a three dimensional
shape that is derived from the product and incorporates
structurally at least part of the product shape.
[0002] The invention further relates to a method of manufacturing a
body suitable for use as a product part in a desired product and
provided with a threedimensional shape that is derived from the
product and incorporates structurally at least part of the product
shape, comprising the steps of:
[0003] providing a foil having a releasable layer and a pattern of
conductor tracks;
[0004] attaching electrical elements to the conductor tracks;
[0005] providing the body of electrically insulating material by a
molding technique, therewith encapsulating the electrical elements
and mechanically anchoring the conductor tracks in the body;
and
[0006] removing the releasable layer.
[0007] Contemporary products increasingly contain electronic
components. Vehicles are full of electronic components that fulfill
sensor functions and allow the operation of task with only a push
on a button. Clothes and other articles are provided with
electronics that can be read out wirelessly. Consumer electronics
products ranging from shavers and coffee-machines to television
sets, remote controls and mobile phones are bodies that include
more functionality than in the past and also need to have a
beautiful shape.
[0008] In order to fulfill the desire of the provision of
electronics anywhere, the electronics can be attached to plastic
parts, including housings that provide the shape of the desired
products and appliances. There are various ways of attachment.
[0009] One of them is the use of a printed circuit board, to which
the electronic components are attached and electrically contacted.
The printed circuit board is provided inside a housing, such that
it is not visible from the outside, or visible only to the extent
that is desired. The disadvantage of the printed circuit board is
however, that it takes considerable space and that it is in need of
substantial assembly. The need for assembly can even limit the
freedom of choosing the shape of the product.
[0010] Another way of attachment is the provision of the
electronics on a label at a surface by means of adhesive. This is
particularly an option wherein the label includes a transponder or
wherein the body is a product part that will be surrounded by a
housing. The use of adhesive however has the disadvantage that it
is not always very robust. Moreover, electrical contacting of the
components is not made easy, since it must be done either
contactlessly or with a limited number of contacts.
[0011] In short, there is a need for such macroscopic bodies as
housings and products parts in or to which any desired electronic
components can be provided in a mechanically stable manner without
limiting the freedom of design of the product shape.
[0012] It is therefore a first object of the invention to provide
an electronic product of the kind mentioned in the opening
paragraph, in which electronics are integrated without limiting the
freedom of the designer and without making the body or the product
mechanically or chemically vulnerable.
[0013] This object is achieved in that the body comprises an
electrically insulating material and comprises a pattern of
electrical conductors, which pattern includes contact pads for
external contacting, that are exposed at a surface, which
conductors are mechanically anchored in the body, a plurality of
electric elements being encapsulated in the body and being
electrically connected to the pattern of electrical conductors.
[0014] According to the invention, the electric elements and the
pattern of conductors are embedded in the body. The body therewith
does not only provide a structural shape of the product and/or to
provide an esthetically desired appearance and/or a mechanical
support for the product. The body is in fact also the encapsulation
for the electric elements and functions as the circuit board for
the attachment of electric contacts for external contacting.
[0015] It is an advantage of the body of the invention that its
manufacture can be very straightforward and is hardly in need of
assembly. Generally, the process flow of the manufacture includes a
first step in which a foil is provided with a releasable layer and
thereon the pattern of conductors. In a second step this foil is
provided at a desired location in a mould and is overmoulded by the
electrically insulating material in the desired shape. In a third
step the releasable layer is removed from the body of electrically
insulating material. The mechanical anchoring of the conductors is
for instance achieved in that the releasable layer is slightly
etched before provision of the molding material, such as to create
underetch. A suitable combination of materials is the use of copper
for the pattern of conductors and the use of Al for the releasable
layer. This has the advantage that both the patterning of the
copper conductors and the removal of the releasable layer can be
realized with wet-chemical etching without deteriorating the other
layers.
[0016] In principle, the complete pattern of conductors will be
present at the surface of the body. Some additional steps may be
taken however, that lead to the encapsulation of the conductors
inside the body. First of all, a foil or spring assembly or
alternative electrical connectors may be connected to the contact
pads before the molding and be partly overmoulded together with the
formation of the body. This provides a very robust integration of
such a connector in the body. An alternative connector is for
instance a connector to which a battery can be connected. Secondly,
the pattern of conductors may be overmoulded in a separate step
after the provision of the body. Thirdly, and particularly in
combination with the use of the underetch for the anchoring, the
pattern may include conductors with a relatively small and with a
relatively large width. By a suitable choice of the underetch time,
the small conductors can be included completely in the body,
whereas the large ones will at least partially be present at the
surface of the body. In a fourth elaboration, the releasable foil
is substantially removed in a first area before the molding
process, without removing the pattern of conductors in that area.
The conductors in the first area can thereafter be provided with an
encapsulation from all sides.
[0017] The electrically insulating material is preferably a polymer
material, that is suitable for use in combination with molding
techniques, particularly insert molding and has a good chemical and
mechanical stability. Examples include polystyrene, polypropene,
polyvinylchloride, polyphenylene sulfide.
[0018] It is particularly preferred that an additional coating is
provided at the foil so as to improve the adhesion between any
metal and the insert moulded polymer. A first example is the use of
a material that melts on heating. Elements to be attached with
solder balls to the pattern of conductors can first be provided on
this material, that is heated thereafter. This process is further
described in the non-prepublished application WO-IB03/02292
(PHNL020471). A second example is the provision of a coating after
that the elements have been assembled on the pattern of conductors.
The coating can then be provided not only at the interface of the
conductors and the insert moulded material, but also at the
interface of the elements and the insert moulded material. A
suitable class of materials to be used for the coatings are
copolymers. Particularly suitable appear to be vinyl copolymers of
acrylic acid and alkyl acrylates.
[0019] It is furthermore preferred for good encapsulating
properties of the molding material that it comprises fillers for
absorption of moisture. Particularly suitable for this aim are
silica or other metal oxides such as aluminum oxide and magnesium
oxide. These fillers may be porous matrices.
[0020] The use of a foil of a releasable layer and a pattern of
conductors thereon is per se known from EP-A 1,187,205. However,
said application discloses the use thereof for chip scale packaging
of integrated circuits. These are electronic components with
typical dimensions in the order of 3*3 mm.sup.2 or less, and the
shape of the body herein follows the shape of the encapsulated
electronic component. The insulating material is therein provided
with transfer molding. In the present invention, however, the shape
of the body is not based on that of the embedded components, but on
that of the product of which the body is a part. In general, the
dimensions of the body will thus be larger than that of an
integrated circuit, and it will not have the shape of a rectangular
block, such as an integrated circuit. Suitable dimensions are for
instance at least 0.5 to 0.5 cm.sup.2, and often more than 3 to 3
cm.sup.2, and in one or more directions even 10 cm or even 1 m. To
be sure, it is not necessary that the foil will have dimensions
comparable to those of the body.
[0021] The use of such a foil is further known from GB-A 2,229,864
as well as from U.S. Pat. No. 5,738,797. However, the known methods
relate to the manufacture of a circuit board. It is not disclosed
therein, that the circuit board can be used as encapsulation for
electric components. It is not disclosed either, that the circuit
board has a sufficient mechanical stability to act as the
structural element in a product.
[0022] In a preferred embodiment, means are present for mechanical
attachment of a device, component or carrier to the body. As the
skilled person will understand, there is a variety of means that
can be provided as part of the mould. This includes cavities and
throughholes in the first place. It also includes any clamping
means, threads for engagement with a thread of an external
component and any edges, protrusions and corners as desired. The
advantage hereof is that the electronic product can be a truly
integrated system, wherein some elements are present at the surface
of the body and others are integrated into the body. An example
hereof is for instance a display, wherein the display is present at
the surface, but wherein the display driver is hidden inside the
body. Another example is for instance a radio: the loudspeaker is
present at the surface, and the electronics are hidden inside the
body. Such electronics do not only include passive components such
as resistors, capacitors and inductors and protective components
such as diodes, but also signal processing units. However, such
signal processing unit could be integrated also with one of the
elements at the surface, as is the case with an image sensor.
Furthermore, with a small radio, it is an advantage that any
electronics or user functionality needed in addition, such as a
display or buttons can be part of the same product. Either they are
integrated in the body, or they are present at the surface that has
a shape fitted for mechanical attachment. It is even possible that
such electronics or functionality is partly overmoulded and thus
anchored in the body.
[0023] Particularly in this embodiment, the body acts as system
integrator of various elements and components. It provides
mechanical stability and shape. This is done not only in that the
product has at least partly the shape of the body, but also in that
any components attached to the body are given their position.
Moreover, due to the versatile possibilities of the molding
process, not only the position, but also the angle with respect to
the surface of the body can be determined. This is particularly
relevant for the optimal operation of microphones, cameras,
displays and the like.
[0024] In a further embodiment, the electronic device comprises a
sensing or transmitting first element provided at the surface of
the body for radiation of a first kind and an auxiliary second
element for processing or providing of the radiation, the first and
second element having a predetermined spatial interrelationship to
each other to allow their functioning, which is defined in the
body, the first element being electrically connected to the pattern
of electrical conductors in the body. The number of electronic
devices being constructed from a first and a second element that
need to be in a mutual interrelationship is large. A good example
is a camera with a lens and a image sensor. In this case the body
acts also defines the locations of the individual elements and
therewith achieves the system integration, that previously needed
to be dealt with separately.
[0025] A variety of electronic products is enabled with the
invention. Electronic components could be introduced in the arms of
a chair. Also, the electronics needed for switching and for power
conversion in a coffee machines or a water boiler could be
integrated in that part constituting a leg of the machine. In the
example of a mobile phone or a remote control, the body may be a
product part with a display and to which any buttons and any
further RF electronics are attached afterwards. The product part
can finally be provided with a separate housing. In the example of
a dashboard the body of the dashboard will be the main structural
part, as it currently is. The body is of course not only suitable
for a dashboard at the front side of a vehicle, but can also be
used at the doors and back side.
[0026] The invention also relates to a body for use in the product.
Circuit boards included in a plastic part of a certain shape are
for instance known from GB-A 2,229,864. In this embodiment the
pattern of conductors is bent so as to provide any required shape.
However, the known circuit board does not include any electric
elements, and it appears disadvantageous to do a bending operation
either before or after the placement of elements on a foil.
Nevertheless, a full flexibility of the required three-dimensional
shape of the body is desired, such that the body can function as
the system integrator giving mechanical support. It is therefore a
second object of the invention to provide a body that fulfills
these objects.
[0027] This second object is achieved in a body suitable for use as
a product part in a desired product and provided with a
threedimensional shape that is derived from the product and
incorporates structurally at least part of the product shape, which
body comprises an electrically insulating material and comprises a
pattern of electrical conductors, which pattern includes contact
pads for external contacting which conductors are mechanically
anchored in the body, a plurality of electric elements being
encapsulated in the body and being electrically connected to the
pattern of electrical conductors, wherein the conductors are
present at a surface only partially.
[0028] In the invention, the conductors are present at the surface
of the body only at certain areas, whereas in other areas they are
hidden inside the body. There are particularly two methods for
achieving this functionality. First of all, the pattern of
conductors may be overmoulded in a separate step after the
provision of the body. This is a simple and straightforward
implementation, however, with the limitation that the products need
to be brought back into a mold after removal of the releasable
layer, and with the limitation that the molding of the additional
features may not affect the shape of the already moulded body
negatively.
[0029] In a second, preferred method, the releasable foil is
substantially removed in a first area before the molding process,
without removing the pattern of conductors in that area. The
conductors in the first area can thereafter be provided with an
encapsulation from all sides.
[0030] Although not preferred in assembly, it nevertheless may be
that the surface of the body includes a first and a second face
which mutually includes an angle unequal to 180.degree. C. and
wherein the pattern of conductors extends along the first and the
second face. This is particularly suitable if the pattern of
conductors comprises a plurality of tracks are positioned in
parallel and need to be fitted to the desired shape. It is
furthermore suitable, if electric components need to be attached
and contacted at different faces, particularly at opposed
faces.
[0031] In another embodiment, the pattern of conductors includes
contact pads for contacting a component that can be assembled to
the surface of the body, and the shape of the body is fitted for
assembly of the active device. For many applications, it is
advantageous that any further active devices can be assembled to
the surface of the body. Examples of such active devices are
integrated circuits and other such semiconductor devices, which may
be too expensive for integration in the body; display devices,
speakers, microphones and lenss that need to be provided at the
surface of the body in order to fulfill their functions; and other
devices for which integration is not preferred.
[0032] In a further elaboration hereof, the surface of the body is
provided with a cavity in which the active device fits. In this
manner the active device is given a mechanical protection.
[0033] The invention further relates to a method of manufacturing a
body suitable for use as a product part in a desired product and
provided with a threedimensional shape that is derived from the
product and incorporates structurally at least part of the product
shape.
[0034] It is a third object of the invention to provide such a
method with an improved freedom of design of the product shape.
This object is achieved in that it comprises the steps of:
[0035] providing a foil having a releasable layer and a pattern of
conductor tracks, the pattern comprising an first area that is to
be hidden in the body;
[0036] removing the releasable layer from the first area to the
extent that any conductor tracks;
[0037] attaching electrical elements to the conductor tracks;
[0038] providing the body of electrically insulating material by a
molding technique, therewith encapsulating the electrical elements
and mechanically anchoring the conductor tracks in the body;
and
[0039] removing the releasable layer to the extent that it is
present at a surface of the body.
[0040] In this method, integration is achieved by suitably
patterning the releasable layer before provision of the mould. This
leads to an efficient method with a good result.
[0041] The removal of the releasable layer before the insertion
into the mold is preferably done by cutting. This results therein
that the releasable layer is also integrated in the body. That is
not problematic if the releasable layer is not too thick.
Furthermore, it has the advantage that the first area is provided
with some mechanical stability after the cutting. Alternatively,
other methods such as localized dry of wet etching or irradiation
with ultraviolet light could be used. The type of removal is also
dependent on the specific foil in use. The releasable layer can in
principle be a layer of a metal, such as Al, Cu, or steel, organic
material, and a ceramic material such as glass or silicium. The
resolution of the patterning is preferably in the range of
millimeters to centimeters. However, with an automation of the
local patterning higher resolution can be achieved.
[0042] The method has its main benefit if also electric elements
are integrated in the body, but is in principle also applicable for
a body without any embedded electric elements.
[0043] Another aspect of the invention resides in an electrically
insulating body that comprises a flexible portion. Such a flexible
portion may be used for a specific connection to a component, so as
to adapt the body to the desired shape or to act as a contacting
portion. Such is flexible portion is achievable in that the
insulating material is provided in more than one step, in each of
which steps desired insulating materials are used, such that a
first portion is provided with an elastic insulating material and a
second portion is provided with a hard, non-elastic insulating
material.
[0044] Examples of non-elastic materials are thermoharders,
epoxides, standard injection molding materials such as
polyphenylenesulfide, polystyrene, nylons, polyester PET, PBT and
PCT, polyetherimide, polyethersulphone, polyarylsulphone,
polysulphone, polyetherketone, polyetheretherketone. The materials
may be strengthened with glass fibers or desired particles as known
to the skilled person. Particularly they are provided with any
cross-linking agent which rigidifies the a structure and is
initiated by heating. Examples of elastic materials are
thermoplastic materials without or substantially without any such
cross-linking agent. Particularly suitable are polyimide and
benzocyclobutene. Any other elastic and non-elastic materials will
be apparent to the skilled person.
[0045] As compared to the body known from GB-A 2,229,864 it is a
clear advantage that the resulting body is fitted for many more
shapes. This is particularly suitable for integration of the body
is a casing with limited space. It is also advantageous with bodies
of larger dimensions, particularly if the body has a
threedimensional shape derived from the product in which it is
used. The edges of the body may be made flexible, therewith
reducing any damage to the body when inserted in a casing. An
intermediate portion between a first and a second rigid portion may
be flexible, so as to allow bending of the rigid portion with
respect to each other. Alternatively, a mainly flexible body may be
provided with rigid portions, at which it can be mechanically and
electrically contacted.
[0046] In a suitable embodiment, the flexible portion is provided
with conductors according to a desired pattern. The flexible
portion has the same function as a flexfoil, but need not to be
assembled to it. Therewith, a problem of electrical contacting is
reduced substantially.
[0047] The body according to this aspect of the invention, is
preferably provided with conductors that are present at a surface
of the body at least partially. As explained above, the conductors
may be hidden in the inside of the body in various ways. It is
furthermore preferred that the conductors are mechanically
anchored, so as to provide a good adhesion between conductors and
the body. It may well be that the pattern of conductors extends
over a first and a second face of the body, or even extends to a
third face opposed to the first face.
[0048] In many applications it will further be preferred that any
electrical elements are embedded in the body. Examples of elements
include diodes, resistors, capacitors, inductors, transformers,
integrated circuits. Therewith the body, having a three dimensional
shape and including the desired elements is really a system of its
own, that does not need any wireless transmission of energy and
data, but can make use of conventional galvanic coupling.
[0049] The electronic device can be used for many applications.
Applications in the field of mobile communication, consumer
electronics and automotive electronics are particularly preferred
in view of the miniaturization and increase of functionality in
those areas. Any components attachable to the body are particularly
components that provide a user interface, and components that are
too vulnerable or expensive or else to be integrated. The body can
be provided with any cavities, holes and other mechanical
attachment means for adequate location and attachment of these
components. For their electric contacting, they will be connected
to the pattern of conductors. Signal processing units may be hidden
in the body. The body can also define the system if two or more
components need a spatial interrelationship for their proper
functioning, such as a lens and an image sensor in the example of a
camera.
[0050] If the flexible portion is used for contacting, it can be
very helpful a connector is present at one end of the flexible
portion or at a rigid portion connected to that end. It is the
advantage of the body of this invention that any suitable connector
can be integrated in the body by overmolding.
[0051] With respect to the manufacturing of this body having a
flexible portion, it is observed that the exact implementation of
such process is open to engineering optimization by the skilled
person. The expression `first mold` and `second mold` is understood
in the context of this application to include both the
implementation with separate moldings and the implementation with
one mold having two or more chambers. For both processes it appears
suitable to use an insertion molding process. As mentioned above,
any additional coatings can be used to improve the adhesion between
metal and the insertion moulded material. The releasable layer is
chosen to desire. Good results have been obtained with a foil with
copper patterns and a releasable layer of aluminum. Alternatively,
the patterns can be of Al, and the releasable layer is of copper.
Copper could be used as well for both the releasable layer and the
pattern of conductors, with a suitable barrier in between of both.
However, silicon and an organic, UV-releasable material could be
used as releasable layers as well.
[0052] These and other aspects of the invention will be further
explained with reference to the figures, in which identical
components have been given the same reference numerals and in
which:
[0053] FIG. 1 shows a first embodiment of the body in a
diagrammatic perspective view;
[0054] FIG. 2 shows a first embodiment of the device comprising the
body shown in FIG. 1 in a diagrammatic perspective view;
[0055] FIG. 3 shows a first embodiment of the body in a
diagrammatic perspective view; and
[0056] FIG. 4 shows a first embodiment of the device comprising the
body shown in FIG. 3 in a diagrammatic perspective view.
[0057] FIG. 1 shows a first embodiment of the electrically
insulating body 2 according to the invention. FIG. 2 shows the
corresponding electronic device 10. The body is manufactured in the
following manner. First a carrier plate is provided, which
comprises a first releasable layer, here with a thickness of 30
.mu.m and made of Al, on which a second, electrically conductive
layer is present. The second layer is in this case made of copper
and has a thickness of 10 .mu.m. This second layer is patterned
into conductors through a mask of silicon oxide by etching with an
aqueous solution of ferrichloride. This solution leads also to some
etching of the Al, leading to underetch under the conductors.
[0058] Hereafter, in this embodiment, the carrier plate is bent in
the desired shape and provided in the mold. Electric elements, such
as resistors, capacitors and diodes, and optionally also integrated
circuits can now be provided on the conductors. Solder is used to
provide an electrical connection between the conductors and the
electric elements, but anisotropically conducting adhesive can be
used alternatively. Then, any suitable synthetic resin, for
instance PPS (=PolyPhenylene Sulphide) is injected in the mold and
the body 2 is formed by injection molding. Finally, the releasable
layer of the carrier plate is removed.
[0059] The body 2 of this example is made to be suitable for a
variety of active devices that are to be assembled at the surface
of the body. This procedure yields not only openings 20, but also a
cavity 60 with a side 61 and a bottom 62, the conductor pattern
extending up to the bottom 62. The cavity 60 is suitable for
accommodating elements such as a loudspeaker 63 and a buzzer 64, as
shown in FIG. 2. The openings 20 are suitable for the formation of
cameras, that are constructed through the assembly of a lens 40 and
a photosensitive semiconductor element 30. The two cameras are
positioned in opposite directions, for which reason the conductor
pattern extends from the first side 2A via the second side 2B to
the third side 2C.
[0060] The shape of the body 2 is not derived from the size of the
components, but from the product in which it has to be used. This
body is made to fit in the upper part of a mobile phone, in the
area above the display. Although not shown in this embodiment, it
can be provided with clamping means to be attached more easily to
the housing of the mobile phone.
[0061] FIG. 3 shows a second embodiment of the body 2 of the
invention. FIG. 4 shows the corresponding device 10. The body in
this example is the carrier for a large number of desired
electronic elements of a mobile phone. These are in particular the
elements which provide the interface to the user. The shape of the
body 2 is chosen such that it forms the basic carrier plate of any
components in the mobile phone. To this body 2 not only the desired
electronic elements can be attached, but also any RF part of the
mobile phone can be attached.
[0062] At the rear side 2C (not shown) of the body 2, conductors 1
provide interconnections between the elements, and connection
regions are present for the placement of elements which implement
the required control functions. It is also possible for a
contacting region for a flexible foil or a connector to be defined
at that side. Connections are present for a semiconductor element
30 of a camera, a loudspeaker 63, a buzzer 64, a display 65, keys
66, a touchscreen 67, lamps 68 (preferably light-emitting diodes)
and a microphone 69. The areas for these elements are indicated in
FIG. 9 by their reference numerals followed by A (for example 30A).
It is noted that the body has the advantage that a direct
connection between (the semiconductor elements 30 of) the cameras
and the picture screen 65 and the keys 66 and/or the touchscreen 67
is also possible without connections having to be realized by means
of connectors or flexible foils. The number of connections may thus
be advantageously reduced, and the camera 41 and the picture screen
65 can be mutually attuned in the assembly.
[0063] It is further noted that the conductors 1 in this embodiment
lie in a recess at a side, whereby possible damage is prevented.
Such damage, however, is improbable anyway when such a
manufacturing method is used (with the underetched copper
conductors) that leads to a recessed position of the conductor
pattern.
[0064] The conductor pattern providing the drive of the touchscreen
67 comprises a flexible portion in this embodiment. This is formed
in that a portion of the carrier plate is provided with an elastic
synthetic resin such as polyimide instead of PPS. Connectors and
flexible connections between two portions of the body 2 can also be
integrated in this manner.
[0065] It is further noted that although not explicitly shown, the
body is very suitable for integration of electric elements that are
needed for a proper operation. Examples hereof are capacitors,
resistors, transformers, diodes for ESD protection, transistors and
other switches, and possibly also integrated circuits such as a
display driver.
[0066] It is also noted that the threedimensional shape of the
shown conductor pattern is not absolutely necessary. A simpler
version which extends in only two dimensions can be made as well.
Moreover, part of the conductors can be provided inside the body in
a simple way, in that the carrier plate is substantially cut away
at those areas in which the conductors need to be embedded in the
body. The cutting is done such that the conductors are separated
from each other. The resulting conductors will be embedded in the
body including the releasable layer. The resulting body can thus
have the shape to accommodate the active devices as good as
possible and to be suitable for integration in and attachment to
the housing of the apparatus, in this case a mobile phone.
* * * * *